FLAME TREATMENT MEETS QUALITY MANAGEMENT

摘要

Flame treatment is used since 50 years as a method of improving the adhesion on plastic andpaperboard surfaces. The range of applications is as wide as the range of plastics processing itself, itis used for pretreatment of bottles and containers, household parts, automotive components, medicalproducts as well as in web applications such as blown and cast film pretreatment, laminations andpaperboard treatment prior to extrusion coatings.The treatment is effected by direct exposure of the substrate to a gas flame for a short period oftime. The flame carries some excess oxygen, which takes part in the combustion, buildingintermediate products in form of active ions such as hydroxyl and carboxyl groups. These ions arebound into the surface, thus building polar groups, which enable a reaction with the coating to beapplied. Therefore, flame treatment is not a heat application, but the controlled use of a chemicalproperty of the flame.The parameters, which define the efficiency of the treatment, are:1.The burner design2.The air/gas-ratio of the flame3.The power output of the burner4.The distance from the burner to the surface5.The speed or the dwell time of the flame on the substrate